Unitensioned drum



1936- c. M. AU-MILLER UNITENSIONED DRUM Filed April 29, 1935 2Sheets-Sheet 2 M W M m a a a n h a I E Patented Nov. 17, 1936 UNITEDSTATES PATENT DFFIQE Application April 29,

7 Claims.

This invention relates to musical instruments, and more particularly toimprovements in instruments of the type embodying a vibratory head orheads, such as drums, banjos, tomtoms, kettle drums or the like. This isa further improvement over my co-pending application Ser. No. 751,641,filed Nov. 5, 1934.

An object of this invention is to provide in a musical instrument ofthis type a single operating means whereby the vibratory head or vellummay be adjusted as to tension.

Another object of this invention is to provide a tensioning means ofthis kind which is contained substantially entirely within theinstrument, the tensioning means being of such a character as not toaffect the tonal qualities of the instrument.

A further object of this invention is to provide a tensioning means ofthis type which is exceedingly simple in construction so as not only topermit the manufacture and assembly of the. instrument at a relativelysmall cost, but also to provide a means which will not get out of orderduring the playing of the instrument and which will also not unduly addweight to the instrument, the tensioning means being in fact of suchsimple construction as to lighten the weight of the instrument.

A still further object of this invention is to provide a tensioningmeans of this kind whereby substantially all of the usual projectinghead tensioning members may be eliminated and the exterior of theinstrument may thereby be made relatively smooth, as well as to providefor a trimmer and neater appearance.

Still another object of the invention is to provide for an improvedmeans for attaching and holding the flesh hoop or ring of a drum orsimilar instrument to facilitate the removal and replacement of the skinor vellum fastened or held by the flesh hoop which forms the head of thedrum.

Yet still another object of this invention is to provide a headtensioning means which is so constructed that the head of the instrumentmay be quickly mounted or removed thereby making it possible for aplayer to carry an extra head which in the event of damage to one head,or the head on the instrument, may be quickly substituted with but avery slight loss of time, as where the head of the instrument breaksduring the playing thereof and which in ordinary instruments wouldrequire a considerable amount of time to replace and subsequentlytension.

1935, Serial No. 18,900

My invention is illustrated in the accompanying drawings, in which,

Figure 1 is a plan View of a drum, part in elevation to show the headtensioning mechanism as it appears from the top.

Figure 2 is a perspective of the key or crank for operation of the headtensioning mechanism.

Figure 3 is a cross sectional view along the line 3-3 of Figure 1.

Figure 4 is a cross sectional View along the line in 4-5 of Figure 1.

Figure 5 is a view in transverse cross section of the operatingmechanism.

Figure 6 is a fragmentary View in cross section of a modification of myinvention. 35

For the purpose of illustrating my invention I shall describe theinvention as applied to the drum shown in the. drawings, it of coursebeing understood that it may be applied to other like instruments.

Referring more specifically to the drawings and as my invention is thesame construction at both ends, a description of one end Will sufiice.It consists of a drum with a head l6, a drum shell or barrel Ill havingits rims at each end turned over inwardly at H so as to form a roundedor enlarged portion over which to stretch the skin or vellum or drumhead IE to prevent cutting of the skin and forming a groove or track Ha.The groove Ha acts as a track or guide for the upper or outside edgeportion of the sliding ring Hi. The sliding ring it is held within thegroove I la of the turned in portion H by pins l3 which are fastened toa band lZa fitting on the outside of the drum shell or barrel ID. Theband I 2a has a bent over portion 27 around its upper periphery adaptedto project within the groove of a grooved annulus i2 stamped from onepiece of metal and fitting around the band I20. mounted on the outsideof the drum shell or barrel 10. The bent over portion 2'? of the bandHat is engaged within the groove of the said grooved annulus l2 and heldcomparatively snug within the groove of the annulus I?! by means of aflesh hoop E5. The flesh hoop l5 besides serving to hold the drum velluml 6 serves to wedge against the top of bent over portion 2! and againstthe opposite inner side of the groove of grooved annulus i2. This snugengagement of the hoop 15 within the groove of the annulus l2 permitsmovement to be transmitted without undesirable play from the band 52a tothe grooved annulus 12. This transmitted movement is obviously madepossible by means of the bent over portion 2'! of band l2a engagedwithin the groove of annulus l2 and contacting 55 a side of the fleshhoop I5 for upward movement and by contacting a side of the groove ofannulus I2 for downward movement. By this arrangement the groovedannulus I2 and the band In move together practically as one unit. Theband I2a carries pins I3 that project through longitudinal slots 28 inthe drum shell I8 and into elongated arc shaped slots 26 cut into thesliding ring I4 at an angle so as to provide curved cam surfaces 22. Thesliding ring I4 is substantially opposite the band I2a and the groovedannulus I2 so as to provide for uniform movement of the pins I3 and thebands I2 and I2a.

Fitted snugly within the groove of the annulus I2 with the turned overportion 21 of band I2a is a flesh hoop I5, which tensions the .drumvellum wfound thereon by the movement transmitted thereto from the slidering I4 to the pins I3 engaged within the arc-shaped slots 26 of ring I4and the band I20. to the grooved annulus which holds the flesh hoop I5.

The grooved annulus I2 is split transversely at 24 with fastening meansor bolts 38 on each side of the split to hold the annulus I2 inoperating position, as shown in Figure 3, to permit ready removal andreplacement of a flesh hoop I5 and the drum skin I6 which is fastenedthereto.

Figure 6 illustrates a modification of the slide ring I4. The slide ringMe as shown in the modification is for the purpose of making the saidslide ring stronger and more rigid whereby to permit the use of lightermaterials by turning the inner end of the ring I4a inwardly of the drumshell Illa at substantially right angles to form a flange 46. The slidering I40. operates in identically the same manner as the slide ring I4in Figures 1, 2, 3, and 4. The only difference being the addition offlange 46. As is indicated, the modified slide ring M11 is guided bygroove IIb when sliding movement is transmitted thereto through the pinsI3a secured to the band I2a, said pins being in engagement with thearcuate shaped slots 22a. The band I2c also transmits movement to thegrooved annulus I2b through bent over portion 21a, whereby the drumvellum IBa is tensioned, It is to be noted that in describing Figure 6,I have for the purpose of clearness attempted to use the same numeralsas far as possible with letter additions. The flange 46 must not projecttoo far inward of the drum shell I8 so as to inter fere with theoperating mechanism shown in Figures 1, 3, 4, and 5.

The operating mechanism which causes the slide ring I4 to slide aroundwithin the shell Ill, guided by track Ila, consists of a gear wheel I8,with discs 38 and 3| mounted on each side of gear wheel I8. The discs 30and 3I are threaded to fit a threaded curved rod I1 and carry the gearwheel I8 along the rod. The gear I8 and the discs 30 and 3I are fastenedtogether by small pins 38 and mounted between brackets 39 and 48 so thatthe gear will move and the discs will thread along the curved rod I!supported by braces 32 and 33 together. The discs 30 and 3| are mountedin sockets or holes in each bracket, 39 and 48, by means of hub likeportions M and 42 formed on one side of each disc to act as the turningpoint or axle for the gear and the attached thereto, as shown in Figure5. The pins 38 beside holding the three parts together also hold thehubs H and 42 of the discs in place in the brackets 39 and 40.

Fitted through the thickness of the drum shell I8 is a shaft 41,hereinafter called the worm drive, having a worm gear 34 on one end tomesh with the gear I8 and a square shank 35 on the other end for cranksocket 36a. The shaft 41 is further provided with shoulder 31 whichrests against the inner side of shell I8, and a reduced portion 45 atits other end fitted in socket 43 formed in cross piece 44 as a part ofbrackets 39 and 40 to permit the worm drive to be freely turned by crank36a.

In operation the crank socket 36a is placed over the shank 35 andturned, say to tighten the drum head. This results in the rotation ofthe worm drive which meshes with the teeth of gear I8, thereby causingit to rotate together with the discs 30 and 3| and thread the curved rodI1 fastened to the slide ring I4 in one direction. As

the two discs 30 and 3I and gear I8 feed the rod II around in the drumshell, ring I4 is caused to slide around within the drum shell. Theslide ring I4 which is caused to slide around the interior of the drumshell I 0 by threaded rod II has are shaped slots 26 cut through itsthickness at an angle or diagonal its width into which flt the pins I3that are fastened to band I2a. These slots will present a. curvedsurface to the pins I3 and as the ring I4 slides in a fixed path around5;

the drum shell will cam against the pins and force them downward. Theresult is the transmission of like downward motion to the band I2a, andthe grooved annulus I2 which carries the flesh hoop I5 and drum skin I5,for they are all linked together for uniform movement and thus the drumskin becomes tightened. To loosen the drum skin the crank is turned inthe opposite direction.

While I have described and shown a drum in the drawings, I wish itunderstood that my invention will apply equally as well to any othertype of vibratory instrument and I claim the right thereto accordingly.

What I claim is:

1. A drum comprising a slotted shell, a drum head mounted on the shell,a hoop to hold the drum head, a guide formed from the shell at an end ofsaid shell, a band mounted outside the shell near an end of the shell, agrooved annulus engaging the said band and the said hoop, pins carriedby the said band projecting inwardly through the said shell, a slidering loosely mounted within the said shell with an edge thereof bentinwardly and the other edge engaging the guide at an end of the shell,cam surfaces formed in the said slide ring, said pins engaging the saidcam surfaces and means inside the shell to move the slide ring aroundwithin the shell to move the said pins, whereby the elements on theoutside of the shell are moved to tension the drum head.

2. A vibratory instrument comprising a shell, 8. vibratory head on anend of the shell, a hoop for said vibratory head, a grooved annulusengaging the hoop, a head tension band adapted to engage the groovedannulus, pins formed inwardly of the head tension band, a slide ringwith arc-shaped slots therein mounted inside of said shell, said pinsengaging the arc-shaped slots of the slide ring and means mounted insidethe shell to transmit movement to said slide ring, whereby to transmitmovement to the said head tension band and grooved annulus to tensionthe vibratory head.

3. A drum comprising a drum shell, a vibratory head on an end of theshell, a hoop for said vibratory head, a grooved annulus engaging thehoop, a head tension band adapted to engage the grooved annulus, pinsformed inwardly of the head tension band, a slide ring with arc-shapedslots therein mounted inside of said shell, said pins engaging thearc-shaped slots of the slide ring and a worm drive mounted inside theshell engaging the slide ring operating means mounted on the said slidering, whereby movement is transmitted to said slide ring and the headten sion band to tension the drum head.

4. A vibratory instrument comprising in combination a drum shell withlongitudinal slots formed therein and a guide around its rim, a drumhead mounted on the shell, a slide ring with cut out curved cam surfacesmounted within the drum shell engaging the said guide, a grooved annulusloosely mounted outside the said shell, a band mounted outside the saidshell opposite the slide ring mounted within said grooved annulus, aflesh hoop carried by the groove of the grooved annulus, said bandhaving pins projecting inwardly through said longitudinal slots of thedrum shell to cooperate with the curved cam surfaces of the said slidering, a curved threaded rod carried by said slide ring, a gear wheelmounted within the drum shell, discs mounted on each side of the gearwheel, pins projecting through the said gear wheel and discs, said gearwheel and discs being rotatably mounted between brackets within the saidshell on said curved threaded rod, braces inside the drum shell tosupport the curved rod, said discs each having hublike portions engagingthe brackets, a shaft extending through the shell, a worm gear on oneend of the shaft in mesh with said gear wheel carried by the discs andmeans on the other end of said shaft to rotate the same, whereby motionis transmitted from one element to the other to tension the drum head.

5. A drum comprising a slotted drum shell rounded at an edge to form aguide, a drum head mounted over the rounded edge portion of the drumshell on a flesh hoop, a head tension band mounted outside the shell, anoutwardly bent over portion around the upper periphery of said band, agrooved annulus mounted around the said head tension band engaging thesaid bent over portion of the head tension band and the said flesh hoop,pins mounted on the inner diameter of the head tension band adapted toprotrude through the drum shell, a slide ring mounted inside the drumshell engaging the said guide opposite the head tension band, curved camsurfaces formed from the said slide ring contacting the said pins and arod carried by said slide ring, a worm drive having a portion thereofprojecting outside the drum shell for engagement with a crank and inengagement with said rod, whereby sliding movement may be transmitted tothe slide ring to move the elements mounted outside the drum shell totension a drum head mounted on the drum shell.

6. A drum comprising a drum shell, a drum head mounted on the shell, aloosely mounted head tension band, a loosely mounted grooved annulus, ahoop for the drum head engaged by the grooved annulus, pins mounted onthe head tension band to engage a slide ring inside the drum shell, saidslide ring having a portion bent inwardly along an edge for rigidity,cam slots formed in said slide ring in engagement with the pins mountedon the head tension band and means mounted on the slide ring forengagement with means mounted inside the drum shell adapted to move thesaid slide ring around within the shell, whereby movement is transmittedto the loosely mounted elements to tension the drum head.

7. A drum comprising a slotted shell, a drum head mounted on the shell,a hoop to hold the drum head, a guide formed from the shell at an end ofsaid shell, a head tension band mounted outside the shell near an end ofthe shell, a grooved annulus engaging the said head tension band and thesaid hoop, pins carried by the said. head tension band projectinginwardly through the slots of the shell, a cam slotted slide ringloosely mounted within the said shell and guided by the shell, said pinsengaging the cam slots of the said slide ring to support the said slidering and means inside the shell to move the slotted slide ring aroundwithin the said shell to move the pins vertically, whereby the elementson the outside of the slotted shell are moved vertically with the pinsto tension the drum head.

CLEVE M. All-MILLER.

